#include<stdio.h>
#include<malloc.h>
#define MaxSize 100
typedef char ElemType;
typedef struct
{   ElemType data[MaxSize];
    int top;
}SqStack;
void InitStack(SqStack * &s)
{ s=(SqStack * )malloc(sizeof(SqStack));
  s->top=-1;
}
void DestroyStack(SqStack * &s)
{
	free(s);
}
bool StackEmpty(SqStack * s)
{
	return(s->top==-1);
}
bool Push(SqStack * &s,ElemType e)
{   if(s->top==MaxSize-1)
       return false;
    s->top++;
    s->data[s->top]=e;
    return true;
}
bool Pop(SqStack * &s,ELemType)
{   if(s->top==-1)
       return false;
    e=s->data[s->top];
    s->top--;
    return true;
}
bool GetTop(SqStack * s,ElemType &e)
{   if(s->top==-1)
       return false;
    e=s->data[s->top];
    return true;
}